Indie auteur Ry Russo-Young broadens her horizons without forgetting where she came from in this strong YA adaptation.

The beauty of being a high school senior in your second semester is that it can seem like nothing matters for a minute. Friendships have been sealed, college applications have been submitted, and everyone is fully aware that the end of summer is going to shake things up like an etch-a-sketch, forcing them to start over from (what feels like) scratch. For a lot of teens — particularly the privileged ones — that brief period of time is a perfect storm of personal agency and emotional recklessness. Never again will they have so little responsibility, either to themselves or to each other.

It’s enough to make someone feel invincible, enough to make them feel like things are going to be this way forever.

Ry Russo-Young’s smart and sensitively told “Before I Fall” takes that idea as literally as possible, but it’s for that reason that her film is ultimately able to pry something powerful from its trite premise. The movie might be little more than a “Groundhog Day” remake set in high school (a description that feels both reductive and right), but if you’re going to make a ripoff of “Groundhog Day,” then high school is one hell of a place to set it.

Adapted from Lauren Oliver’s 2010 YA novel of the same name, “Before I Fall” takes a little while to arrive at its premise — for the first 30 minutes or so it feels more like a somber and straitlaced riff on “Mean Girls” than anything else.

Samantha Kingston (“Everybody Wants Some!!” breakout Zoey Deutch) is our Lindsay Lohan, and she’s pretty much at the top of the food chain. Beautiful, smart, and grounded, you know she’s the heroine because her character feels like more of a person than she does a type. That’s more than enough to make Sam stand out in her posse of self-described “bitches,” a fearsome foursome who radiates that classic get-out-of-their-way-when-we-walk-down-the-hallway-in-slow-motion swagger. There’s Lindsay, the merciless bully with model looks (Halston Sage), Ally, the shy girl who’s sheepish about her smarts (Cynthy Wu), and Elody, the wild one who’s afraid that she’ll be kicked out of the group if she isn’t constantly acting like the life of the party.

Sam, meanwhile, is not as perfect as she seems. She’s short with parents, she’s dating the douchiest bro in school even when she’s dismissive of the nice guy (Logan Miller) who harbors an obvious crush on her, and she’s happy to join her friends in cruelly teasing the school’s token outcast, Juliet (Elena Kampouris), a wild-haired blonde girl who jolts the film into magical-realism and generally acts as though she were raised by wolves.

But all of that is about to change, and not just because Sam is planning on losing her virginity to her braindead boyfriend at the big “Cupid Day” party. The party is a bust, the girls get into a huge scuffle with Juliet, and their car is sideswiped during the drive home, presumably killing Sam and all of her friends. Cut to: Sam waking up earlier that same morning, sent back to the beginning of the day that she died. Again, and again, and again.

The first few rotations are a bit grim, too stale and derivative to sustain interest for viewers old enough to have seen this formula at work before. But suffer through the first half and you’ll find that things get considerably more interesting as Sam begins to make sense of her situation and go rogue, and the momentum only snowballs as her story loops towards its big ideas.

“Before I Fall”

“Before I Fall” leans hard into its anachronistic genre trappings; the “Twilight”-era YA tropes are too deeply baked into the source material for Russo-Young to extricate this story from them, and she’s smart enough not to try. Instead, she embraces them, milking the novel’s gloomy Pacific Northwest setting for all of its teenage melodrama and its characters for all of their hyper-earnest narcissism.

The director — an indie stalwart who doesn’t forget her cooler sensibilities as she wades into broader territory for the first time — walks a very fine line between the capriciousness of the high school movies of the ’90s and the supernatural mawkishness of the ones that have dominated the last few years, and she does so with a gracefulness that allows her to borrow from the best of both worlds. With a massive assist from Deutch’s exquisitely nuanced lead performance (she creates a heroine who cycles between self-obsession, self-destruction, and self-improvement without ever sacrificing the sense that she’s a real person), Russo-Young creates a film that feels both grounded and enchanted, a film that feels a lot like high school.

Flecked with lyrical imagery and representing both Grimes albums on the female-driven soundtrack, this is a movie that mines real depths of feeling from its deceptively shallow premise. It’s a model for how indie filmmakers can revitalize mainstream fare.

Russo-Young insists upon “Before I Fall” maintaining the courage of its convictions, and she gets her way — the movie takes a while to get off the ground, but when it lands, it lands hard. Ambushing its anti-bullying message rather than attacking it head on, Sam’s circular journey resolves as a surprisingly sharp story about the impact that we have on other people, even if we’re not there to see it for ourselves.